JP4185960B2 - Working device and working method for circuit board - Google Patents

Description

  The present invention relates to a working apparatus and a working method for a circuit board that performs a predetermined work related to mounting of an electronic component on a circuit board on which the electronic component is mounted.

  In the mounting process of electronic components, the process of applying and printing a conductive paste or solder cream on the work surface of the circuit board (hereinafter referred to as the board surface), the circuit board surface of the circuit board on which the conductive paste or the like has been applied or printed The process of mounting electronic parts on the board, the process of mechanically and electrically joining the electronic parts to the circuit board by thermocompression bonding or reflow, the process of dicing each circuit board if the circuit board is a multi-chip board, etc. Thus, various operations (or processing) are performed on the circuit board. In order to improve the mounting quality of electronic components in these processes, it is important to manage the work height (working height) when working on the circuit board, and to realize highly accurate work height management. For example, an electronic component mounting apparatus disclosed in Patent Document 1 is known.

  According to what is disclosed in this patent document 1, the deviation (displacement amount) of the board surface on which the electronic component is mounted from the mounting reference plane is measured, and the deviation of the board surface is approximated using this deviation. By calculating the correction amount of the mounting height when mounting electronic components on the board surface, and correcting the mounting height based on this correction amount, the electronic component mounting surface is pressed against the board surface without excess or deficiency. Can be implemented.

JP 2000-299597 A

  However, in the electronic component mounting apparatus disclosed in Patent Document 1, since the warpage shape of the entire board surface is virtual based on the amount of displacement from the work reference surface at an arbitrary location on the board surface, the circuit board as a target If there is a discontinuous surface due to the effect of a step, a slit, a notch or the like, there is a possibility that a warped shape separated from the actual surface shape of the substrate surface may be imagined due to an increase or decrease in local displacement. When the mounting height is corrected based on the correction amount calculated based on the virtual warp shape in this way, the mounting surface of the electronic component cannot be pressed into contact with the substrate surface without being insufficient, and the mounting quality is deteriorated. The problem arises. The problem of the deterioration of the mounting quality is the same for the quality of work when performing various work on the circuit board.

  Accordingly, an object of the present invention is to solve the above-described problem, and in a work for a circuit board that performs a predetermined work related to mounting of the electronic component on the circuit board on which the electronic component is mounted, Provided is a working device and a working method for a circuit board that can be maintained without degrading the quality of work on the circuit board even when there is a discontinuous surface due to the effects of steps, slits, notches, etc. There is.

  In order to achieve the above object, the present invention is configured as follows.

According to the first aspect of the present invention, at least three measurement points set on the work surface of the circuit board and a plurality of auxiliary measurement points set in the vicinity of each of the measurement points, A measuring means for measuring a measurement displacement amount from the work reference plane;
The difference between the maximum value and the minimum value of the measured displacement from the work reference plane at the measurement location measured by the measurement means and the auxiliary measurement location set in the vicinity of the measurement location is equal to or less than a threshold value. And determining the shape of the work surface of the circuit board by a curved surface model based on the measured displacement amount for each of the measurement points determined to be equal to or less than the threshold value, and Calculating means for calculating the calculated displacement amount of the curved surface model from the surface;
A working device for a circuit board, comprising: a correcting means for correcting a work height when working on the work surface of the circuit board based on the calculated displacement amount of the curved surface model calculated by the calculating means. I will provide a.

  According to the second aspect of the present invention, the calculated displacement amount at each measurement location of the curved surface model calculated by the calculation means is compared with the measurement displacement amount at each measurement location, The circuit board according to the first aspect, further comprising compatibility determination means for determining whether the curved surface model is compatible by determining whether the difference between the two is equal to or less than a threshold and determining that the difference is equal to or less than the threshold. A working device is provided.

  According to a third aspect of the present invention, the computing means changes the shape of the partitioned work surface based on the measured displacement amount for each partitioned work surface obtained by partitioning the work surface of the circuit board into a plurality of regions. Provided is a working device for a circuit board according to a first aspect, which is assumed by a curved surface model.

According to the fourth aspect of the present invention, at least three measurement points are set on the work surface of the circuit board,
For each of the set measurement points, measure the measurement displacement from the work reference plane of the circuit board,
Determine whether the measured displacement amount for the measured measurement point is qualified as a sampling displacement amount,
If the measurement points that have been determined not to be qualifying exists, and sets a new measurement point instead of the constant-position measurement it is determined not to be the qualified, the measured displacement amount of the new measurement point the measured, upper Symbol measured displacement amount is determined whether qualify as sampling displacement,
If it is determined that the eligibility for all the measurement points, based on the measured displacement amount of the determined the measurement point as a qualified, by surface model the shape of the working surface of the circuit board Assuming that the calculated displacement amount of the curved surface model from the work reference surface is calculated,
A work method for a circuit board that performs work on the circuit board by correcting a work height when working on the work surface of the circuit board based on the calculated displacement amount of the calculated curved surface model. I will provide a.

According to the fifth aspect of the present invention, when setting the at least three measurement points , set at least one auxiliary measurement point in the vicinity of each of the measurement points,
When measuring the measurement displacement amounts of the respective, it performs measurement of the measurement displacement amount for each of the auxiliary measurement point above,
In determining the eligibility of the measurement displacement, the measuring points of the respective, maximum and minimum values of the measurement points and the respective measuring displacement of the set the auxiliary measurement locations in the vicinity thereof According to a fourth aspect of the present invention, there is provided a work method for a circuit board, which determines that the circuit board is eligible when the difference between the two is less than or equal to a threshold value.

According to the sixth aspect of the present invention, after the curved surface model is assumed, it is determined whether or not the assumed curved surface model and the work surface of the circuit board are suitable,
If it is determined not to fit, in addition to the at least three measurement points, and set the new measurement point, assume a new the surface model using each of the measurement points, the A working method for the circuit board according to the fourth aspect is provided.

  According to the seventh aspect of the present invention, in determining the compatibility between the assumed curved surface model and the work surface of the circuit board, the calculated displacement amount at each measurement location of the curved surface model, and the respective A working method for a circuit board according to a sixth aspect is provided, wherein the measurement displacement amount at the measurement point is compared and it is determined that the difference is equal to or less than a threshold value, so that the circuit board is suitable.

  According to the eighth aspect of the present invention, in the assumption of the curved surface model, for each partition work surface obtained by partitioning the work surface of the circuit board into a plurality of regions, the shape of the partition work surface based on the measured displacement amount. Is provided by the curved surface model, and a working method for the circuit board according to the fourth aspect is provided.

  According to the present invention, it is possible to accurately correct the work height assuming a curved surface model approximated by the shape of the board surface on which the work is performed on the circuit board. Even if there is a discontinuous surface due to the influence of a notch or the like, it can be maintained without degrading the quality of work on the circuit board.

Before continuing the description of the present invention, the same parts are denoted by the same reference numerals in the accompanying drawings.
Embodiments according to the present invention will be described below in detail with reference to the drawings.

(First embodiment)
FIG. 1 shows a schematic plan view of an electronic component mounting apparatus 101 which is an example of a working device for a circuit board according to the first embodiment of the present invention, and FIG. 2 shows a partial schematic side view thereof.

  First, the overall configuration of the electronic component mounting apparatus 101 according to the first embodiment will be described with reference to FIGS. 1 and 2. In the present invention, the working device for the circuit board means that various work (or processing) is performed on the work surface (hereinafter referred to as the board surface) of the circuit board while managing the work height (or processing height). In the first embodiment, the substrate surface is managed while managing the mounting height, which is the height distance between the circuit board substrate surface and the work tool (or the electronic component held by the work tool). An electronic component mounting apparatus for mounting electronic components will be described as an example.

  In the electronic component mounting apparatus 101 of FIG. 1, a conveyance guide 2 is disposed at a substantial center on the base 1. The conveyance guide 2 functions as a substrate positioning unit that conveys the circuit board 3 on which electronic components are mounted and positions the circuit board 3 at a predetermined position. In the first embodiment, the conveyance direction of the circuit board 3 is the X direction, and the direction orthogonal to the circuit board 3 in the horizontal plane is the Y direction. On both sides of the conveyance guide 2 in the Y direction, component supply units 4 are arranged, and a plurality of parts feeders 5 are detachably arranged in parallel. A pair of Y tables 6 are disposed at both ends of the base 1 in the X direction. An X table 7 is installed on these Y tables 6, and moves in the Y direction by driving the Y table 6. A transfer head 8 is disposed on the side of the X table 7 and moves in the X direction by driving the X table 7. A camera 9 and a height detection sensor 10 are disposed on the side of the transfer head 8. The camera 9 functions as a recognition unit that captures an image of the lower part and recognizes the position of the electronic component or the circuit board 3, that is, the position in the XY plane. The Y table 6 and the X table 7 function as horizontal moving means for horizontally moving the transfer head 8, the camera 9, and the height detection sensor 10 to arbitrary positions on the base 1. A line camera 11 is disposed between the conveyance guide 2 and the component supply unit 4.

  In FIG. 2, the transfer head 8 has a plurality of nozzle units 12 arranged in parallel (in the first embodiment, for example, three nozzle units 12 are arranged in a line). At the lower end portion of each nozzle unit 12, a nozzle 13 that picks up and picks up the electronic component P from the parts feeder 5 is mounted. In the first embodiment, each nozzle 13 is an example of a work tool that performs a work of mounting electronic components on the circuit board 3. Each nozzle unit 10 includes an elevating device 12a that elevates and lowers the nozzle 13 in the Z direction. The electronic component P is placed on the substrate by lowering the nozzle 13 and pressing the lower surface of the electronic component P against the substrate surface 3a. 3 is implemented. The Z direction is a direction orthogonal to the X direction and the Y direction.

  The height detection sensor 10 detects the height of the substrate surface 3a, that is, the position in the Z direction, by projecting a laser beam onto the measurement spot s on the substrate surface 3a and receiving the reflected light. A detection result by the height detection sensor 10 is subjected to calculation processing in the calculation unit 14, and a displacement amount d (hereinafter referred to as a displacement amount) d of the measurement location s from the work reference plane 3b is measured. Thus, the height detection sensor 10 and the calculation unit 14 function as a measurement unit that measures the amount of displacement of the measurement location s from the work reference surface 3b. The work reference surface 3b is a substrate surface 3a in a state in which the flat circuit board 3 that is not warped or deformed is positioned by the transport rail 2, and the electronic components P are not excessively or deficient on the work reference surface 3b. The lowering stroke of the nozzle 13, that is, the mounting height is set so that the mounting can be performed by pressing. Therefore, when the circuit board 3 is warped or deformed, the board surface 3a and the work reference surface 3b do not coincide with each other. Therefore, when the electronic component P is mounted on the circuit board 3, it is necessary to correct the mounting height. There is. For example, as shown in the explanatory diagram of FIG. 3A, the board surface 3a of the circuit board 3 is deformed into a convex shape with respect to the work reference surface 3b, that is, is curved so that the end of the circuit board 3 is positioned below. In this case, the upward displacement amount d1 is the mounting height correction amount, and is subtracted from the mounting height set corresponding to the work reference surface 3b. On the other hand, as shown in the explanatory diagram of FIG. 3B, when the substrate surface 3a is deformed in a concave shape with respect to the work reference surface 3b, that is, when the end portion of the circuit substrate 3 is curved and deformed. The downward displacement amount d2 becomes the correction amount of the mounting height, and is added to the mounting height set corresponding to the work reference surface 3b. Thus, when correcting the mounting height, it is necessary to measure the amount of displacement of the substrate surface 3a from the work reference surface 3b. Therefore, in the first embodiment, a curved surface model that approximates the shape of the substrate surface 3a in the circuit board 3 is assumed, and the mounting height is corrected based on the displacement amount from the work reference surface 3b in the curved surface model. .

  In FIG. 2, the control unit 15 functions as a correction unit that corrects the mounting height based on the amount of displacement of the curved surface model stored in the storage unit 17 from the work reference surface 3b, and controls the driving of the lifting device 12a. As a result, the lowering stroke of the nozzle 13 is adjusted to correct the mounting height. The storage unit 17 includes a storage area in which various data, control programs, and the like are stored in addition to the curved surface model. The input unit 16 inputs a control signal to the control unit 15 and inputs data and programs to be stored in the storage unit 17.

  Next, the procedure for correcting the mounting height assuming a curved surface model will be described with reference to the flowchart shown in FIG. When assuming a curved surface model, first, a plurality of measurement locations are set on the board surface 3a of the circuit board 3 (step ST1). As shown in FIG. 5A, which is a partial schematic plan view of the substrate surface 3 a of the circuit board 3, measurement points (exemplifying s 1 to s 4) are set on the substrate surface 3 a with XY coordinate values by the input unit 16. Alternatively, an arrangement pattern stored in advance in the storage unit 17 may be selected. Further, when the size and type of the circuit board 3 and the number of measurement locations are input by the input unit 16, an optimal arrangement pattern can be selected. In order to assume a curved surface model as will be described later, it is preferable to set at least three points that are not located on the same straight line as such measurement points, for example, four corners on the circuit board 3. It is more preferable to provide in the vicinity of the part and the intermediate point thereof.

  Next, at least one auxiliary measurement location is set in the vicinity of each measurement location set in step ST1 (step ST2). The auxiliary measurement location is set for each measurement location set in step ST1. That is, the auxiliary measurement location is associated with one measurement location and set in the vicinity thereof. 5B, which is a partial schematic plan view of the substrate surface 3a, shows an example in which an auxiliary measurement location is set in the vicinity of one measurement location s1 among the measurement locations (s1 to s4 are illustrated) shown in FIG. 5A. . The auxiliary measurement points are set at a total of four points, sx1 and sx2 in the X direction and sy1 and sy2 in the Y direction, with the measurement point s1 as the center. The number and arrangement of the auxiliary measurement points can be selected and set as appropriate, but it is more preferable to set the measurement points in the four directions as in the first embodiment. The auxiliary measurement location can be set by an XY coordinate value by the input unit 16 or may be selected from an arrangement pattern stored in advance in the storage unit 17. Further, when the number and arrangement of auxiliary measurement points are input by the input unit 16, a suitable arrangement pattern can be selected. Although not shown in FIG. 5B, for each of the other measurement points s2, s3, and s4, four auxiliary measurement points are set in the vicinity thereof.

  Next, the displacement amount is measured for the measurement location and the auxiliary measurement location set in steps ST1 and ST2 (step ST3). As described above, the measurement of the displacement amount is performed by calculating the detection result of the height detection sensor 10 by the calculation unit 14, and the measured displacement amount is an auxiliary set for each measurement location and the measurement location. The amount of displacement at the measurement location is set in one group and temporarily stored in the storage unit 17. In the example shown in FIG. 5B, a total of five displacement amounts at one measurement point s1 and four auxiliary measurement points sx1, sx2, sy1, and sy2 associated with the measurement point s1 are set and stored in one group. . Similarly, the other measurement locations s2, s3, and s4 are stored as a set with the displacement amount at the auxiliary measurement location set for each measurement location in step ST2.

  Next, a determination is made as to the suitability of the displacement measured in step ST3 as the sampling displacement (step ST4). In this determination, the difference between the maximum displacement amount and the minimum displacement amount is calculated for each group of displacement amounts stored in the storage unit 17, and the difference between the maximum displacement amount and the minimum displacement amount is compared with a predetermined threshold value. To do. The predetermined threshold value is stored in the storage unit 17 in advance, and is set to, for example, 0.3 mm in the first embodiment. If the difference between the maximum displacement amount and the minimum displacement amount within each displacement amount group is less than or equal to a predetermined threshold value, the displacement amount at the measurement location included in this group is determined to be eligible as the sampling displacement amount. The displacement amount at the measurement location is selected as the sampling displacement amount when assuming the curved surface model (step ST5).

  If the difference between the maximum displacement amount and the minimum displacement amount in the displacement amount group is larger than a predetermined threshold value, it is determined that the displacement amount at the measurement location included in this group is ineligible as the sampling displacement amount. In other words, the difference between the maximum displacement amount and the minimum displacement amount within the group is larger than a predetermined threshold, which means that there is no local step, slit, notch, etc. between the measurement location and the nearby auxiliary measurement location. This means that there is a high possibility that a continuous surface exists, and if a displacement at such a measurement location is selected as the sampling displacement in the assumption of a curved surface model, local variations are reflected in the approximation of the shape of the substrate surface. Therefore, there is a possibility that a curved model far from the actual shape of the substrate surface is assumed. Therefore, when the difference between the maximum displacement amount and the minimum displacement amount in the group is larger than a predetermined threshold, the measurement location included in this set is invalidated and a new measurement location is set in the vicinity of the measurement location ( Step ST6).

  In the setting of a new measurement location, it is possible to set the XY coordinate value on the substrate surface 3a by the input unit 16 in the same manner as the setting in step ST1, or automatically set from the arrangement pattern stored in the storage unit 17 in advance. You may make it do. Also for the newly set measurement point, the setting of the auxiliary measurement point (step ST2), the measurement of the displacement amount (step ST3), and the determination of suitability (step ST4) are performed. If it is determined in step ST4 that the displacement at the new measurement location is qualified as the sampling displacement, the displacement at the new measurement location is selected as the sampling displacement (step ST5).

  As described above, the displacement amount in the discontinuous surface such as the local step, the slit, and the notch on the substrate surface 3a is not set as the sampling displacement amount for assuming the curved surface model. Does not affect the assumption of the curved surface model. As a result, a curved surface model approximated by the actual shape of the substrate surface 3a is assumed, and the mounting height corrected based on the amount of displacement of the curved surface model from the work reference surface 3b is adjusted to an appropriate height, so that the mounting quality is improved. Leads to improvement.

  Next, a curved surface model is assumed based on the displacement adopted as the sampling displacement in step ST5 (step ST7). The curved surface model is assumed by analyzing the warpage and deformation tendency of the entire substrate surface 3a based on the sampling displacement amount and formulating it. FIG. 6 shows a curved surface model 20 that assumes a substrate surface 3a that is warped and deformed in a convex manner with respect to the work reference surface 3b. The curved surface model 20 is converted into a mathematical formula and stored in the storage unit 17, and all locations on the curved surface model 20 are represented by an XYZ coordinate system. The computing unit 14 functions as computing means for computing the amount of displacement of the curved surface model 20 from the work reference surface 3b, and can compute the amount of displacement from the work reference surface 3b for all locations of the curved surface model 20. For example, a Z coordinate value zm, which is a displacement amount in the XY coordinate value (xm, ym) of the curved surface model 20, is calculated from the XY coordinate value (xm, ym) of an arbitrary mounting location m on the circuit board 3. The mounting height is corrected as a correction amount when the Z coordinate value zm is mounted on the board surface 3a.

Specifically, the assumption of such a curved surface model is that the calculation unit 14 uses the curved surface equation z = f (x, y) to the XY coordinates (x, y) of each measurement location on the circuit board 3 and its displacement ( This is performed by substituting the measured displacement amount z). As a comparatively simple example, when assuming a curved surface model in which displacement occurs in the Y direction, the equation of the curved surface can be expressed by a quadratic function z = ay ² + by + c, and data of at least three measurement points is obtained. By inputting, three unknowns (a, b, c) can be obtained. Furthermore, when assuming a curved surface model in which displacement occurs in the X direction, a curved surface model can be assumed by using a curved surface equation corresponding to the curved surface model. Although it is possible to calculate an equation representing a curved surface model by performing specific calculations in this way, in order to perform more efficient calculation, a plurality of types of curved surface equations prepared in advance are prepared. Alternatively, for example, the curved surface model may be assumed by selecting an approximate curved surface equation closest to the calculation result (previously stored in the storage unit 17).

  Next, the compatibility between the curved surface model 20 and the substrate surface 3a is determined (step ST8). This determination is based on the amount of displacement (measured value (measured displacement amount) at a plurality of measurement points adopted as the sampling displacement amount, as to how much the difference exists between the curved surface model 20 and the substrate surface 3b assumed in step ST7. )) And the displacement amount (calculated value (calculated displacement amount)) in the curved surface model 20 calculated from the XY coordinate values of the measurement location.

  If it is determined that the difference between the calculated values (calculated displacement amounts) is less than or equal to a predetermined threshold value for all actually measured values (measured displacement amounts), the curved surface model 20 is determined to be compatible with the substrate surface 3a, and the displacement of the curved surface model 20 is determined. The mounting height is corrected based on the amount (calculated displacement amount) (step ST9). The predetermined threshold value is stored in advance in the storage unit 17, and is set to, for example, 0.3 mm in the first embodiment. On the other hand, when the difference between the actually measured value (measured displacement amount) and the calculated value (calculated displacement amount) is larger than a predetermined threshold value, it is determined that the curved surface model 20 does not match the substrate surface 3b. In such a case, a new measurement location is additionally set in the vicinity of the measurement location where the measured value exceeds the predetermined threshold (step ST10), and the number of measurement locations is increased for more details. By acquiring simple sample data, the curved surface model 20 more suitable for the shape of the substrate surface 3a is assumed again. For newly added measurement locations, auxiliary measurement locations are set in step ST2, and after measuring the respective displacement amounts in step ST3, the displacement amounts measured in step ST4 are adapted as sampling displacement amounts. A determination is made whether or not After the curved surface model 20 is assumed, if it is determined again in step ST8 that the newly assumed curved surface model 20 is suitable for the substrate surface 3a, the assumption of the curved surface model 20 is completed, and the newly assumed curved surface model 20 is obtained. The mounting height is corrected based on the displacement amount (step ST9). Note that such suitability determination is performed in the calculation unit 14, and the calculation unit 14 functions as a suitability determination unit.

  In FIG. 7, which is a schematic diagram showing how the electronic component is mounted at the mounting position of the circuit board 3, the mounting height when the electronic component P is mounted at an arbitrary mounting location m on the substrate surface 3 a is h3. . Therefore, as shown in FIG. 6, the correction amount h2 is calculated by calculating the displacement amount zm of the curved surface model 20 from the XY coordinate values (xm, ym) of the mounting location m, and adjusted with respect to the work reference surface 3b. The mounting height h3 is calculated by performing correction by subtracting the correction amount h2 from the mounting height h1. At the mounting position of the circuit board 3, the nozzle 13 that sucks and holds the electronic component P by the mounting height h <b> 3 corrected in this way is lowered by the elevating device 12 a, and the electronic component is passed through the bonding material (for example, solder material). The electronic component P can be mounted on the circuit board 3 with high accuracy by pressing P against the circuit board 3.

  Accordingly, by checking the compatibility between the assumed curved surface model 20 and the substrate surface 3b in this way, the curved surface model 20 approximated by the actual shape of the substrate surface 3a is assumed, and the work reference plane of the curved surface model 20 is assumed. The mounting height corrected based on the amount of displacement from 3b is adjusted to an appropriate height, which leads to an improvement in mounting quality. In addition, since the number of measurement points is reduced at the start of the assumed work to improve efficiency, the measurement points can be additionally set only when they do not fit, and a more accurate curved surface model 20 can be assumed. Can be corrected efficiently and accurately.

  The predetermined threshold value is set to 0.3 mm in step ST4 and step ST8 because the electronic component is pushed onto the circuit board by the nozzle 13 lowered for mounting the electronic component by driving the lifting device 12a. This is because an amount of about 0.3 mm is required as the amount (the amount to be pushed in at the time of pressing), so that an error of about 0.3 mm is allowed for the displacement amount of the substrate surface 3a. Therefore, it is preferable to set a predetermined threshold according to the amount of pressing of the nozzle 13 as needed in order to improve the mounting quality.

  Next, a substrate work processing system configured by including a plurality of work devices (hereinafter referred to as substrate work devices) for circuit boards as typified by the electronic component mounting apparatus 101 of the first embodiment will be described. This will be described with reference to a schematic explanatory diagram shown in FIG. In FIG. 8, the substrate work processing system is configured by arranging a plurality of substrate work apparatuses in the order of processes. The substrate working device 30 located at the uppermost stream of the process includes a height detection sensor 10, a calculation unit 14, a control unit 15, and a storage unit 17, and a mathematically curved surface model stored in the storage unit 17. The amount of displacement from the work reference plane is calculated by the calculation unit 14, and the control unit 15 corrects the work height based on the amount of displacement to perform a predetermined work process on the substrate surface. The storage unit 17 of the substrate working device 30 is communicably connected to a control system including the calculation unit 14 and the control unit 15 provided in the substrate working devices 31, 32, and 33 disposed on the downstream side of the process. . The substrate working devices 31, 32, and 33 calculate the displacement amount of the mathematically curved surface model stored in the storage unit 17 of the substrate working device 30 from the work reference plane in each computing unit 14, and based on the displacement amount. Each control unit 15 corrects the work height to perform a predetermined work on the substrate surface.

  In this way, in the substrate work processing system provided with a plurality of substrate work devices for performing predetermined work processing on the substrate, another substrate work device based on the curved surface model assumed in at least the substrate work device positioned at the most upstream of the process By correcting the work height in step 1, the mounting height is corrected by the same curved surface model in all the steps of performing various operations on one substrate, leading to improvement in work quality. Further, it is economical because the measuring means such as the height detection sensor 10 need only be provided in at least the most upstream substrate working apparatus. Furthermore, since it is not necessary to measure the substrate surface for each process, it is possible to shorten the work time in each apparatus, which is efficient.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. FIG. 9A is a schematic plan view showing a circuit board handled in the working device for the circuit board of the second embodiment, and FIG. 9B is a plan view showing a state in which the board surface of the circuit board of FIG. 9A is divided into a plurality of regions. It is. In the first embodiment, the entire board surface 3a of the circuit board 3 is assumed to be a single curved surface model 20, but in the second embodiment, the board surface 53a of the circuit board 53 is divided into arbitrary regions. The difference is that the shape of each section screen is assumed by a curved surface model, and the shape of the entire substrate surface 53a is assumed by using these curved surface models. Only the differences from the first embodiment will be described below.

  FIG. 9A shows a circuit board 53 in which slits 53c that are a plurality of openings are formed. When assuming a curved surface model of the substrate surface 53a having a discontinuous surface such as the slit 53c, the substrate surface 53a is partitioned into a plurality of regions with the position where the slit 53c is formed as a part of the partition line 53d. As shown in FIG. 9B, the substrate surface 53a is partitioned into, for example, three partition screens 53e, 53f, and 53g. For each of the section screens 53e, 53f, 53g, the curved surface model of each of the partition screens 53e, 53f, 53g is assumed in the same manner as the assumption of the curved surface model of the substrate surface in the first embodiment. The lane marking 53d can be set as an XY coordinate value by the input unit 16, or may be selected from the partition patterns stored in advance in the storage unit 17.

  As described above, by combining each curved surface model obtained by dividing one substrate surface 53b into a plurality of section screens 53e, 53f, and 53g, a warped shape having a discontinuous warped shape or a complicated curved surface is assumed. Therefore, it is possible to assume a curved surface model that is more suitable for the substrate surface 53a on which a discontinuous surface due to a step, a slit, a notch, or the like exists. In each of the section screens 53e, 53f, 53g, at least three measurement points are set, and more preferably, measurement points such as the vicinity of each corner and an intermediate position are set to measure the displacement amount and the curved surface. Model assumptions are preferably made.

  In the present invention, the “auxiliary measurement location” means an auxiliary set near the measurement location for the purpose of determining whether or not the displacement measured at the “measurement location” is appropriate as the sampling displacement amount. It is a typical measurement point. Therefore, it is used for determining the suitability and not used for assuming a curved surface model.

  In general, a circuit board includes a resist formation part and an electrode formation part, and these parts have different light reflectivities and the like, and the height data detected by the height position detection sensor is different. Is also possible. Furthermore, the reflectance may be different in a portion where a bonding material such as cream solder is disposed on the circuit board. Therefore, an auxiliary measurement point is set near the periphery of the measurement point, and it is determined whether or not the displacement amount measured at the measurement point is appropriate. From this point of view, it can be said that the auxiliary measurement point is not preferable even if it is too close to the measurement point or too far away.

  The approaching limit is preferably the minimum electrode formation width formed on the circuit board, for example, 0.3 mm or more. This is because such an electrode is the smallest of the uneven portions formed on the circuit board. As the limit of separation, if it is too far away, the original purpose of supplementing the measurement value at the measurement location cannot be achieved. Therefore, for example, it is preferably set within 5 mm, and at most within 10 mm.

  Further, in the electronic component mounting apparatus 101 of the first embodiment, when the electronic components are continuously mounted on the same type of circuit board, the first circuit board loaded is used. As described in the first embodiment, the measurement location and the auxiliary measurement location are set and the curved surface model is assumed, and the second and subsequent circuit boards are set as the first circuit board. The measurement location can be set at the same position as the measured location, and the curved surface model can be assumed without setting the auxiliary measurement location. In the first circuit board, if the eligibility as the sampling displacement amount of the measurement location is determined, setting the measurement location at the same position in the subsequent circuit board can skip the above eligibility determination step. Because it can. In such a case, it is possible to efficiently assume a curved surface model.

  Further, in each of the above embodiments, the case where the working device for the circuit board is an electronic component mounting device has been described as an example. However, such a working device applies solder cream to the work surface of the circuit board.・ Coating / printing equipment for printing, joining equipment for mechanically and electrically joining electronic components to circuit boards by thermocompression bonding and reflow, and dicing into individual circuit boards when multiple circuit boards are used The present invention can also be applied to a dicing apparatus that performs the above.

  Next, useful contrivance points by carrying out in combination with the working methods for the circuit boards of the respective embodiments will be described below.

  If the circuit board is formed of, for example, a relatively soft material and the amount of warpage becomes large, the circuit board and other components and circuit boards that are disposed or operate above the conveyance path of the circuit board and its holding position May interfere with the other. In order to prevent such a problem in advance, after assuming a curved surface model, the amount of warping of the circuit board is determined by comparing with a preset threshold value, so that there is a possibility of interference with other components. A circuit board having a large amount of warpage is specified, and an error display of work processing is output. As a result, it is possible to stop the work process for a circuit board having a large amount of warpage and to prevent actual interference with other components.

  Moreover, the method of further improving the height detection accuracy by the height detection sensor which detects the height of a measurement location by projecting a laser beam can be combined with said each embodiment. Specifically, a vacuum sensor is provided in the vacuum suction path of the nozzle for sucking and holding the electronic component, and the nozzle located at a certain height is gradually lowered while performing vacuum suction. Thereafter, the timing at which the vacuum pressure in the vacuum suction path significantly increases is detected by the vacuum sensor, and the value of the encoder in the nozzle lifting device at this timing is acquired. Such timing is the timing at which the tip of the nozzle comes into contact with the board surface of the circuit board, and the encoder position can be used to detect the height position of the board surface of the circuit board at the time of nozzle contact. . Next, the height position of the board surface is detected by the height detection sensor at the same position on the circuit board. Next, using the height position detected using the vacuum sensor of the nozzle as a reference, the difference from the value detected by the height detection sensor is calculated and stored as an offset correction amount. By correcting the production data (original data) itself using such an offset correction amount, it is possible to correct the measurement value by the height detection sensor and to assume a curved surface model with high accuracy. For example, when the height detected by the height detection sensor is 1.5 mm and the height position detected by the nozzle is 1.7 mm, the offset correction amount is +0.2 mm, and then the height detection sensor A value obtained by adding +0.2 mm to the acquired height position is handled as corrected height position data. In addition, it may replace with the case where the sensor which detects the timing which a nozzle contact | abuts on a substrate surface is a vacuum sensor (pressure sensor), and may be the case where the flow sensor which detects the amount of vacuum suction is used.

  The correction using such an offset correction amount is not limited to the case where the production data (original data) itself is directly corrected as described above. There may be a case where the production position is corrected by detecting the height position using a nozzle for each lot (production group of the same type of circuit board).

  In addition, the detection of the height position using the nozzle is performed on the substrate surface of the circuit board in the group of the flattest surface of each group of the measurement location and the auxiliary measurement location, or the circuit board. It is preferable to perform the measurement at a measurement reference point set in advance.

  It is to be noted that, by appropriately combining arbitrary embodiments of the various embodiments described above, the respective effects can be achieved.

  According to the present invention, it is possible to accurately correct the work height assuming a curved surface model approximated by the shape of the circuit board surface, so that the target circuit board is affected by steps, slits, notches, etc. Even if there is a discontinuous surface due to, it has the advantage that it can be maintained satisfactorily without degrading the quality of work on the circuit board, and electronic parts are mounted by performing predetermined work on the circuit board It is useful in the field.

  Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various variations and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as being included therein, so long as they do not depart from the scope of the present invention according to the appended claims.

  The Japanese patent application No. 10 filed on Nov. 29, 2005. The disclosures of the specification, drawings, and claims of 2005-343272 are hereby incorporated by reference in their entirety.

FIG. 1 is a schematic plan view of the electronic component mounting apparatus according to the first embodiment of the present invention. FIG. 2 is a partial schematic side view of the electronic component mounting apparatus according to the first embodiment. FIG. 3A is an explanatory diagram illustrating a mounting height in the electronic component mounting apparatus according to the first embodiment, and illustrates a state in which an end portion of the circuit board is displaced downward. FIG. 3B is an explanatory diagram illustrating a mounting height in the electronic component mounting apparatus according to the first embodiment, and is a diagram illustrating a state in which an end portion of the circuit board is displaced upward. FIG. 4 is a flowchart showing a mounting height correction operation in mounting the electronic component of the first embodiment. FIG. 5A is a partial schematic plan view showing a measurement location set on the substrate surface of the first embodiment. FIG. 5B is a partial schematic plan view showing auxiliary measurement points set on the substrate surface of the first embodiment. FIG. 6 is a schematic perspective view showing a curved surface model of the circuit board in the first embodiment. FIG. 7 is a schematic side view showing how the electronic component is mounted in the first embodiment. FIG. 8 is an explanatory diagram showing a configuration of a substrate processing system including the electronic component mounting apparatus according to the first embodiment. FIG. 9A is a schematic plan view showing a circuit board on which slits to be handled by the working device for the circuit board according to the second embodiment of the present invention are formed. FIG. 9B is a schematic plan view showing a state in which the substrate surface of the circuit board of FIG. 9A is partitioned into a plurality of regions.

Claims (8)

Measure the measured displacement from the work reference plane of the circuit board for at least three measurement points set on the work surface of the circuit board and a plurality of auxiliary measurement points set in the vicinity of each of the measurement points. Measuring means to
The difference between the maximum value and the minimum value of the measured displacement from the work reference plane at the measurement location measured by the measurement means and the auxiliary measurement location set in the vicinity of the measurement location is equal to or less than a threshold value. And determining the shape of the work surface of the circuit board by a curved surface model based on the measured displacement amount for each of the measurement points determined to be equal to or less than the threshold value, and Calculating means for calculating the calculated displacement amount of the curved surface model from the surface;
A working device for a circuit board, comprising: a correcting means for correcting a work height when working on the work surface of the circuit board based on the calculated displacement amount of the curved surface model calculated by the calculating means. .   The calculated displacement at each measurement location of the curved surface model calculated by the calculation means is compared with the measurement displacement at each measurement location to determine whether the difference between them is equal to or less than a threshold value. The work apparatus for a circuit board according to claim 1, further comprising suitability determination means for determining that the curved surface model is matched by determining that the curve model is equal to or less than the threshold value.   The calculation means assumes the shape of the partition work surface by the curved surface model based on the measured displacement amount for each partition work surface obtained by partitioning the work surface of the circuit board into a plurality of regions. A working device for the described circuit board. Set at least three measurement points on the work surface of the circuit board,
For each of the set measurement points, measure the measurement displacement from the work reference plane of the circuit board,
Determine whether the measured displacement amount for the measured measurement point is qualified as a sampling displacement amount,
If the measurement points that have been determined not to be qualifying exists, and sets a new measurement point instead of the constant-position measurement it is determined not to be the qualified, the measured displacement amount of the new measurement point the measured, upper Symbol measured displacement amount is determined whether qualify as sampling displacement,
When it is determined that all the measurement points are qualified, the shape of the work surface of the circuit board is determined by a curved surface model based on the measurement displacement amount for the measurement points determined to be qualified. Assuming that the calculated displacement amount of the curved surface model from the work reference surface is calculated,
A work method for a circuit board that performs work on the circuit board by correcting a work height when working on the work surface of the circuit board based on the calculated displacement amount of the calculated curved surface model. . When setting the at least three measurement points , set at least one auxiliary measurement point in the vicinity of each of the measurement points,
When measuring the measurement displacement amounts of the respective, it performs measurement of the measurement displacement amount for each of the auxiliary measurement point above,
In determining the eligibility of the measurement displacement, the measuring points of the respective, maximum and minimum values of the measurement points and the respective measuring displacement of the set the auxiliary measurement locations in the vicinity thereof The work method for the circuit board according to claim 4, wherein when the difference is equal to or less than a threshold value, the circuit board is determined to be eligible. After the curved surface model is assumed, it is determined whether the assumed curved surface model and the work surface of the circuit board are compatible,
If it is determined not to fit, in addition to the at least three measurement points, and set the new measurement point, assume a new the surface model using each of the measuring points, wherein Item 5. A working method for the circuit board according to Item 4.   In determining the compatibility between the assumed curved surface model and the work surface of the circuit board, the calculated displacement amount at each measurement location of the curved surface model and the measured displacement amount at each measurement location. The working method for a circuit board according to claim 6, wherein the circuit board is determined to be suitable if the difference between them is equal to or less than a threshold value.   In the assumption of the curved surface model, the shape of the partitioned work surface is assumed by the curved surface model based on the measured displacement amount for each partitioned work surface obtained by partitioning the work surface of the circuit board into a plurality of regions. A working method for the circuit board according to 4.

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